Dry shaver



Jan. 17, 1939. B. R. NYHAGEN 2,143,896

DRY SHAVER Filed Deo. l, 1937 2 Sheejzs-Sheet l ATTORNEYS Jan. 17, 1939. B, R. NYHAGEN DRY SHAVER Filed Dec. l, 1937 2 Sheets-Sheet 2 INVENTOR. .BY rlzgfZ-fhfgew mf@ ATTORNEYS Patented Jan. 17, 1939 yocurran STATES 1 PATENT OFFICE 12 Claims.

This invention relates to electric razors or dry Shavers and refers more particularly to an improvement in cutter heads therefor for a type in which a pair of cutter elements are both mounted for relative reciprocation with reference to each other and a supporting section having fixed relation to a handle or holder.

The invention comprehends a cutter head having inner and outer cutter elements adapted to be simultaneously driven in opposite directions and a base for mounting the same together with a common means which serves to detachably assemble the parts, which means also functions to exert a tension which draws and retains the confronting surfaces of the cooperative cutting teeth of the cutter elements into operative engagement with each other While permitting of the relative reciprocatory movement of the cutter elements with reference to each other and the base.

The invention further resides in a cutter head of the indicated character which is provided with guard members spaced laterally from the teeth of the cutter elements and winch guard members are adapted to be driven coincident with the inner moved with and in the same direction as the outer cutter element which engages the skin to thereby more effectually raise and present the hair to the cutter teeth, while obtaining a more thorough agitation and massage of the skin during the shaving operation.

The invention is also directed to resilient means for cooperation with the guard member to suiliciently tension the same and compensate for any lost motion or Wear to insure a smooth running and noiseless operation of the device.

As a further feature the invention embodies a cutter head which is longitudinally curved to provide a longitudinally convex exterior designed to ilt the armpit so asto facilitate shaving in this region.

The above and other objects are attained by cutter head constructions which are set forth in the following s pecication, illustrated in the accompanying drawings and particularly pointed out in the appended claims.

In the drawings:

Fig. 1 is a vertical longitudinal sectional view through the cutter head of a dry shaver and through a portion of the handle, the same being shown on an enlarged scale.

Fig. 2 is an end view thereof.

Fig. 3 is a transverse sectional view therethrough taken approximately on the line 3.-3 of 55 Eig. 1.

cutter element so that the guard member will bev (Cl. Sli-43) Fig. 4 is a collective perspective view of the parts of the cutter head in separated relation, the same being shown on a relatively reduced scale.

Fig. 5 is an enlarged vertical longitudinal sectional view similar to Fig. 1, illustrating a modi 5 fied form of the invention.

Fig. 6 is an end View thereof.

Referring to the drawings by characters of ref-i erence, A designates generally any conventional type of handle or holder for the cutter head of a dry shaver, which handle or holder houses the usual type of electric motor, not shown, the rotary driven shaft l0 of which motor extends through'the end wall Il of the handle. The end wall is provided with outwardly projecting spaced parallel flanges I2 which dene a groove in which is adapted to be removably positioned the cutter unit which is hereinafter designated generally by the reference character B.

The cutter unit B is composed of a base section l5 which preferably, as shown, is of H-shaped cross sectional configuration defining on its upper or outer surface a longitudinally extending groove or recession I6 and on its under surface a longitudinal groove or recession I1, the web portion I8 of said base having a centrally disposed opening I9 to receive the protruding end of the motor shaft l0.

In addition to the base section, the cutter head B includes a cutter element 20 which is substan tially cross sectionally U-shaped configuration, the lower or inner bight portion 2| of which is mounted for guided reciprocatory movement in the groove or recession I6 of the base section with the leg portions 22 thereof extending outwardly 35 or upwardly. The outermost surfaces or sides of the leg portions are longitudinally grooved as at 23 and are provided with aligned longitudinally extending slots 24 for a purpose to be hereinafter set forth.

The cutter head B further includes a substantially cross sectionally"`T"-shaped cutter element 30, the stem portion 3l of which is mounted for guided reciprocatory movement Within the U- shaped cutter element 2U and the opposite side edges of the head portion 32 of which overlie the ends of the leg portions 22 of said U`shaped cutter element.

The upper or outer ends of the leg portions 22 of the Ushaped cutter element 20 and the head portion 32 of the T-shaped cutter element 30 are provided with complementary cutting teeth 33 and 34 which are adapted to sever the hair as the cutter elements and their teeth are reciprocated.

In order to effectually raise and present the portion 2| of the U-shaped cutter element.

hair to the cutter teeth by stretching and agitating the skin in the region'of the teeth, guard members are provided, the base portions 36 of which are mounted within the grooves 23 on opposite sides of the U-shaped cutter element and the upper or outer portions 31 are offset laterally, spaced from the cutting teeth and notched so as to stretch the skin between the teeth and said guard members when the outer or upper end of the cutter head is in :dat contact with the skin during the shaving operation. i

In order to provide means for reciprocating the cutter elements 2li and 30 with reference to each other and the base i5 which is detachably secured in fixed relation to the handle or holder A by means of a set screw, the motor shaft it is provided with eccentric terminals dit Vand. il which extend through and operatively engage transverse slots 62 and 43 formed in the cutter elements 2li and 30 respectively. Obviously, upon rotation of the motor shaft, the eccentric terminals and 4| will effect relative longitudinal reciprocation of the cutter elements t@ and 3U with reference to each other and the base.

In order to transmit the reclprocatory motion to the guard members 35 so that said guard members move with the outer'or upper cutter element 30 and in an opposite direction to the direction of movement of the inner or lower cutter element 20, transverse pins are provided which extend through notches 46 in the inner or underside of the upper or outer cutter element 3B and through the longitudinal slots -24 in the leg portions 22 of the cutter element 20, the terminals of the pins being secured to the base portions 36 of the guard members.

In order to provide means for detachably assembling the cutter elements with each other and the base section I5, and to exert a tension which draws and retains the confronting surfaces of the cutting teeth into operative engagement with each other while permitting of relative reciprocatory movement of the cutter elements with reference to each other and the base when assembled, latch arms 50 are provided at opposite ends of the base which are rockably carried by leaf springs 5| which are secured as at 52 to the underside of the web portion i8 of the base section, the latch arms extending upwardly through aligned openings 53 and 54 provided in the web portion I8 of the base section and in the bight The latch arms are provided at their upper or outer free ends with toothedterminals 55 which engage with keeper elements 5B at the opposite ends of the T-shaped cutter element. As illustrated, the keeper elements are preferably in the form of rockable fingers which are mounted in recesses 51 in the opposite ends of the stem portion 3| of the T-shaped cutter element 30, the same being fulcrumed on transverse pivot pins 58 and pro'- vided with depending portions 59 having camshaped faces 60 which engage with the transverse pins 45.

Under this construction and arrangement, the springs 5| which exert a downward or inward tension on the latch arms 50, swing the keeper fingers 56 downwardly or inwardly on their fulcrum pins 58 and through the cam surfaces B0 of the depending extensions 59, exert an upward or outward movement of the pins 45 to force and maintain the confronting surfaces of the cutter teeth ll and 34 into intimate shearing contact as the cutter elements are reciprocated in opposite directions by rotation of the motor shaft l0.

In the modied form of the invention illustrated in Figs. 5 and 6 of the drawings, the construction and mode of operation is substantially the same as that set forth for the form of the invention shown in Figs. l to 4 inclusive, with the exception that the T-shaped cutter element 313A is of longitudinally arcuate formation, the outer or upper surface of the head portion 32A thereof being of longitudinally convex form and the lower or inner end of the stem portion @HA being of longitudinally concave form. En this instance, also, the end edges of the leg portions 22A of the iJ-shaped cutter element 20 are of longitudinally arcuate convex formation, while the upper or outer surface of the bight portion 2 iA of the said U-shaped cutter element is of longitudinally arcuate convex forrnation, This disposes the cutting teeth 33A and 34A on an arcuate line adapting the razor to :dt the armpit so as to facilitate shaving in this region. In order to compensate for the longitudinal arcuate movement of the cutter elements 20A and 30A, the slots 24A which receive the transverse pins 45A are also arcuate and struck from a common center coinciding withA the arcs of the cutter elements 20A and 36A.

The guard elements 35A follow the arcuate formation of the cutter elements and the base 35A of each guard element is mounted for guided longitudinal reciprocation in arcuate grooves 28A in the leg portions 22A of the U-shaped cutter element.

What is claimed is:

l. A cutter head for dry Shavers including a pair of interitting relatively longitudinally reciprocable cutter elements having complementary cutting teeth, a base section for mounting the same for reciprocation with reference thereto, keeper means at the opposite ends of one cutter element, and rockable spring pressed latches.

carried by opposite ends of the base and detachably engageable with the keeper means for assemblying the cutter elements with the base and for drawing and maintaining the confronting surfaces of the cutting teeth into engagement with each other.

2. A cutter head for dry shavers including a pair of interfltting relatively longitudinally reciprocable cutter elements having complementary cutting teeth, a base section formounting the same for reciprocation with reference thereto, keeper means pivotally carried by the opposite ends of one cutter element, and rockable spring pressed latches carried by opposite ends of the base and detachably engageable with the keeper means |-for assembling the cutter elements with the base and for drawing and maintaining the confronting surfaces of the cutting teeth into engagement with each other.

3. A cutter head for dry shavers including a substantially cross sectionally H-shaped base, a substantially cross sectionally U-shaped cutter element mounted for guided longitudinal reciprocation in the base with the ends of the leg portions thereof dlsposed outwardly, a substantially cross sectional T-shaped cutter element mounted for guided longitudinal reciprocation in the U-shaped cutter element with the head portion thereof overlying the ends of the leg portions of the U-shaped cutter element, complementary cutter teeth formed on the head portion and ends of the leg portions of said cutter elements, and resilient means for assembling the cutter elements with the base and for drawing and maintaining the confronting surfaces of the cutter teeth into engagement with each other.

4. A cutter head for dry shavers including a substantially cross sectionally H-shaped base, a substantially cross sectionally U-shaped cutter element mounted for guided longitudinal reciprocation in the base with the ends of the leg portions thereof disposed outwardly, a substantially cross sectional T-shaped cutter element mounted for guided longitudinal reciprocation in the U-shaped cutter element with the head portion thereof overlying the ends of the leg portions of Vthe U-shaped cutter element, complementary cutter teeth formed on the head portion and ends of the leg portions of said cutter elements, and resilient means for assembling the cutter elements with the base and for drawing and maintaining the confronting surfaces of the ,cutter teeth into engagement with each other, said means consisting of toothed keepers at the 1ongitudinal ends of the T-shaped cutter element and rockable spring pressed latches carried by the base.

5. A cutter head for dry shavers including a substantially cross sectionally H-shaped base, a substantially cross sectionally U-shaped cutter element mounted for guided longitudinal reciprocation in the base with the ends of the leg portions thereof disposed outwardly, a substantially cross sectional T-shaped cutter element mounted for guided longitudinal reciprocation in the U-shaped cutter element with the head portion thereof overlying the ends of the leg portions of the U-shaped cutter element, complementary cutter teeth formed on the head portion and ends of the leg portions of said cutter elements, and resilient means for assembling the cutter elements with the base and for drawing and maintaining the confronting surfaces of the cutter teeth into engagement with each other, said means consisting of rockable toothed keepers at the longitudinal ends of the T-shaped cutter element and rockable spring pressed latches carried by the base.

6. A cutter head for dry Shavers including a substantially cross sectional H-shaped base provided with longitudinal grooves on opposite surfaces thereof, a substantially cross sectional U- shaped cutter element mounted for guided reciprocatory movement in the groove of one surface of the base and having a longitudinal groove in the outermost surface thereof, cutter teeth at the upper edge portions of said cutter element on opposite sides of the groove, a substantially T-shaped cutter element having its stem portion mounted for guided reciprocatory movement in the groove of the U-shaped cutter element, cutter teeth on the stem portion ofthe T-shaped cutter element overlying the cutter teeth and the lU-shaped cutter element, leaf springs in the remaining groove of the base, latch arms rockably carried by the leaf springs having hooked terminals at their free ends, and keeper means provided at the opposite ends of the T-shaped cutter element with which the terminals of the latch arms are engaged to assemble the cutter elements with the base,I to draw and maintain the confronting surfaces oi' the cutter teeth into engagement with each other and to permit of reciprocatory movement of the cutter elements with reference to the base.

7. A cutter head for dry Shavers including a pair of inner and outer interfitting relatively longitudinally reciprocal cutter elements having complementary cutting teeth, a base section mounting the same for reciprocation with reference to each other and the base, and guard elements having toothed terminals spaced laterally from the cutting teeth and connected to the outer cutter element for reciprocation therewith.

8. A cutter head for dry Shavers including a substantially cross sectionally H-shaped base, a substantially cross sectionally U-shaped cutter element mounted for guided longitudinal reciprocation in the base withV the ends of the leg portions thereof disposed outwardly, a substantially cross sectional T-shaped cutter element mounted for guided` longitudinal reciprocation in the U- shaped cutter element with the head portion thereof overlying the ends of the leg portions of the U-shaped cutter element, complementary cutter teeth formed on the head portion and ends of the leg portions of said cutter elements, resilient means for assemblying the cutter elements with the base and for drawing and maintaining the confronting surfaces of the cutter teeth into engagement with each other, and guard elements having toothed terminals spaced laterally from and alongside of the cutting teeth and connected to the T-shaped cutter element for reciprocation therewith.

. 9. A cutter head for dry shavers including a substantially cross sectionally H-shaped base, a substantially cross sectionally U-shaped cutter element mounted for guided longitudinal reciprocation in the base with the ends of the leg portions thereof disposed outwardly, a substantially cross sectional T-shaped cutter element mounted for guided longitudinal reciprocation in the U- shaped cutter element with the head portion thereof overlying the ends of the leg portions of the U-shaped cutter element, complementary cutter teeth formed on the head portion and ends of the leg portions of said cutter elements, resilient means for assemblying the cutter elements with the base and for drawing and maintaining the confronting surfaces of the cutter teeth into engagement with each other, and guard elements having toothed terminals spaced laterally from and alongside of the cutting teeth and connected to the T-shaped cutter element for reciprocation therewith, the means of connection between said T-shaped cutter element and guard elements consisting of transverse pins anchored at their opposite ends to the guard elements, extending through longitudinal slots in the U-shaped cutter element and engaging notched portions of the T-shaped cutter element.

10. A cutter head for dryshavers including a substantially cross sectionally H-shaped base, a substantially cross sectionally U-shaped cutter element mounted for guided longitudinal recipro- 1 cation in the base with the ends of the leg portions thereof disposed outwardly, a substantially cross sectional T-shaped cutter element mounted for guided longitudinal reciprocation in the U- shaped cutter element with the head portion thereof overlying the ends of the leg portions of the U-shaped cutter element, complementary cutter teeth formed on the head portion and ends of the leg portions of said cutter elements, rockable toothed keepers at the longitudinal ends of the T-shaped cutter element, rockable spring pressed latches carried by the base engageable therewith for assemblying the cutter elements with the base and for drawing and maintaining the confronting surfaces of the cutter teeth into engagement with each other, guard elements having toothed terminals spaced laterally from the cutting teeth, transverse pins anchored ,to the guard members, the leg portions of the U-shaped cutter element having slots receiving said transverse pins, the stem portion of said T-shaped cutter element having notches engaging over said pins for moving the guard elements in unison.

therewith.

11. A cutter head for dry shavers including a substantially cross sectionally H-shaped base, a substantially cross sectionally U-shaped cutter element mounted for guided longitudinal reciprocation in the hase with the ends of the leg portions thereof disposed outwardly, a substantially cross sectional T-shaped cutter element mounted ior guided longitudinal reciprocation in the U- shaped cutter element with the head portion thereof overlying the ends of the leg portions of the U-shaped cutter element, complementary cutter teeth formed on the head portion and ends of the leg portions of said cutter elements, rockable toothed keepers at the longitudinal ends of the T-shaped cutter element, rockable spring pressed latches carried by the base engageable therewith for assemblying the cutter elements with the base and for drawing and maintaining the confronting surfaces of the cutter teeth into engagement with each other, guard elements having toothed terminals spaced laterally from the cutting teeth, transverse pins anchored to the guard members, the leg portions of the U- shaped cutter element having slots receiving said transverse pins, the stem portion of said "i"- shaped cutter element having notches engaging over said pins for moving the guard elements in unison therewith, said guard elements having base portions and the 1ieg portions of said U- shaped cutter element having grooves sliolably receivingsaidbase portions and cam raced terminals on said rockahle toothed keepers adapted to coact with said transverse pins to advance the confronting faces of the cutter teeth at the ends of the leg portions towards the confronting faces of the cutter teeth of the head portion.

i2. A cutter head for dry Shavers including a pair of inner and outer intertting relatively longitudinally reciprocable cutter elements having complementary cutting teeth arranged on an arc, a base section for mounting the same for reciprocation with" reference to each other and the base, keeper means at the opposite ends of one cutter element and rockable spring pressed latches carried by the opposite ends of the base and detachably engaging the keeper means for assemblying the cutter elements with the base to draw and maintain the confronting surfaces of the cutting teeth into engagement with each oher and to permit of longitudinal reciprocation of the cutter elements.

BARNEY R. NYHAGEN. 

